The present invention relates to an improved windshield wiper in which the double blade members with angle difference are mobilely adjusted responsive to the change of the curvature of the windshield so as to always adapt to the curvature and tightly attach thereto at any part during the wiping operation for achieving an improved wiping effect.
FIG. 1 shows a conventional windshield wiper which is composed of a large rib A, two middle ribs B, two small ribs C and a wiper blade D. Each of the ribs is lengthwise pivotally connected with the other in order to tightly and freely adaptably attach the wiper blade to the curved windshield of a car and achieve a satisfactory wiping effect. As shown in FIG. 2, during the operation of the windshield wiper, the position thereof on the curved glass windshield is changed instantaneously and the shape of the wiper is simultaneously changed to meet the varying curvature of the windshield. During each reciprocal movement of the wiper blade, the curvature of the wiper blade is changed periodically. Referring to FIGS. 3 and 4, one end of the large rib A is disposed with a U-shaped channel for the middle rib B to fit thereinto. A plastic pad member E is inserted between the large and middle ribs. The pad member has two lateral lugs which extend from the pad member into the pivot holes of the ribs so as to pivotally connect the ribs with each other. The pad member is plate-like and resilient, permitting the middle rib to lengthwise swing with the end of the large rib serving as a fulcrum.
In operation, the conventional windshield wiper often leaves a not completely wiped area in the wiping face of the windshield. Moreover, even different not completely wiped areas will be left by the same wiper with respect to different kinds of cars. This is because that in the rotational movement, the axial center of the double wiper blades with difference of angle is positioned on a plane glass and the rotary axial center is just located in the same straight line. Therefore, the rotation can be smoothly performed and the wiper blade can be totally opposed against and tightly contact with the glass surface and achieve an optimal wiping effect. However, the windshield of a general car is curved and different brands of cars will have differently curved glass windshield to cooperate with the integral design of the cars. Since the wiper blades are tightly attached to the glass surface, the wiper blades will become curved and thus it is impossible for the double wiper blades with angle difference to directly accomplish the angle shift of axial center rotation at the wiping position. Therefore, such arrangement is not suitable for the general car windshield.